I have just spent the last 30 minutes reconfiguring the contents of my 7MDH, and I managed to squeeze all my stuff in there. I started having my gear in 2-3 different places, and would prefer one centralized location. I would love to keep my 5MDH set for when I just want to grab-n-go, but some days I take the 40D/17-55, and some days I take the XT/Tamron combo, and some days we take both if DH is coming with me.
With the dual set up we have, the 7MDH will not be large enough for storage purposes.

